Electric components mounted in automobiles and the like form electric circuits by connecting to other electric components, power devices, and the like via wire harnesses that bundle insulated wires together. Here, connectors provided on the wire harness and provided on the electric component, the power device, and the like are mated with each other to connect the wire harness to the electric component, the power device, and the like. The interior of each connector is equipped with a connection structure in which a crimp terminal and an insulated wire have a crimp connection.
This connection structure is formed by inserting the insulated wire into the crimp terminal, which has a crimping portion that electrically connects a conductor in the insulated wire, and then swaging the crimping portion. As a result, the crimp terminal and the insulated wire are connected in a conductible manner.
Incidentally, increased functionality and performance in recent electric components has resulted in increasing complexity in electric circuits, and there is thus increased demand for reliable conductivity at crimping connection areas between respective crimp terminals and insulated wires. In opened-barrel type crimp terminals such as those employed thus far, crimping portions and conductors have been exposed, and thus in harsh usage environments, there has been a risk of the crimping portion surfaces and conductor surfaces in the crimping connection areas corroding and causing a drop in conductivity.
In response to such a problem, using the crimp terminal having a closed-barrel type crimping portion disclosed in paragraph [0005] of Patent Document 1, for example, provides a connection structure capable of preventing corrosion of the crimping portion surfaces and conductor surfaces in the crimping connection areas.
The crimp terminal disclosed in Patent Document 2, for example, has been disclosed as a closed-barrel type crimp terminal. The crimp terminal according to Patent Document 2 has a cylindrical crimping portion whose other end is closed on one side of a longitudinal direction, as illustrated in FIGS. 10 to 15 in Patent Document 2. By inserting a tip portion of an insulated wire into the cylindrical crimping portion and crimping the tip portion, it is thought that the crimp terminal according to the Patent Document 2 can ensure reliable conductivity between the crimp terminal and a conductor in the insulated wire and prevent corrosion of the crimping portion surface and conductor surface in the crimping connection area.
However, a crimp terminal having such a form cannot be obtained without being individually manufactured through a method such as casting. In other words, the crimp terminal cannot be manufactured by, for example, punching out a band-shaped copper plate and sequentially bending the copper during transport. Furthermore, connecting the insulated wire and forming the connection structure cannot be carried out while manufacturing the crimp terminal. As such, a closed-barrel type crimp terminal such as that disclosed in Patent Document 2 has had a problem in that the connection structure cannot be continuously and efficiently manufactured.